Article Summary

The following diagram shows you how to wire a common 4-pin 12v relay for use in a vehicle application. It can be used to power high amp circuits such as aux lighting or actuators. 

The H7 bulb is a single filament bulb. It is used on high or low beam headlight applications. It is popular with European cars. Some need speciual adapters to fit properly. 

The h4 headlight bulb is a dual filament bulb that does high and low beam in the same bulb. 

Click here for a list of our H4 LED bulbs. 

The H11 bulb is one of the most commonly used bulbs. It can be used in low beam, high beam , or fog lights on many vehicles.